Coinjection stretch blow molded container

摘要

Coinjection stretch blow molded containers comprising a thermoplastic polyester resin and an EVOH resin are obtained, which have greatly improved impact delamination resistance. The containers comprise a thermoplastic polyester layer (layer <Underline>a</Underline>) and an ethylene-vinyl alcohol copolymer layer (layer <Underline>b</Underline>), with the layer <Underline>a</Underline> being kept in direct contact with the both surfaces of the layer <Underline>b</Underline>, wherein the ethylene-vinyl alcohol copolymer satisfies the following formulae (1) and (2) and its differential scanning calorimetry (DSC) gives a single peak for crystal fusion:<MathDetails id="matha01" num="(1)"><MathText><![CDATA[ <math display="block"><mtext>25 ≤ ETb ≤ 48</mtext></math><img id="ia01" file="imga0001.tif" wi="119" he="9" img-content="math" img-format="tif" /> ]]></MathText></MathDetails><MathDetails id="matha02" num="(2)"><MathText><![CDATA[ <math display="block"><mtext>92 ≤ SDb ≤ 99</mtext></math><img id="ia02" file="imga0002.tif" wi="116" he="9" img-content="math" img-format="tif" /> ]]></MathText></MathDetails> wherein ETb indicates the ethylene content (mol%) of the ethylene-vinyl alcohol copolymer, and SDb indicates the degree of saponification (%) of the ethylene-vinyl alcohol copolymer.